1. Field of the Invention
The present invention relates to a fuel tank structure for use in a vehicle using gaseous fuel such as natural gas.
2. Description of the Related Art
Conventionally, among vehicles using gaseous fuel such as natural gas, there are vehicles on which a large-size fuel tank 100 is mounted as shown in FIG. 16. The fuel tank 100 is usually configured in a cylindrical shape in order to uniformly disperse the pressure of fuel gas contained therein. Since the diameter of the fuel tank becomes large in order to secure a sufficient capacity, a large space such as a room 110 is utilized as a place where the fuel tank is mounted.
A partition plate 111 is provided at the rear side of the fuel tank 100 and the rear side of the partition plate is used as a practical portion for the trunk room 110.
However, since there are many useless spaces at the mounting portion of such cylindrical fuel tank 100 with a large diameter, there arise problems that the space utilization factor is degraded and the space within the vehicle such as the trunk room 110 is reduced to a large extent. Further, when the size of the fuel tank 100 is reduced, there arises a problem that the capacity of the fuel gas inevitably is reduced.
Thus, there is proposed an example (JP-A-2000-219050) wherein the fuel tank 100 is divided into two tanks each having a relatively small diameter and the two tanks are disposed in a manner that the outer peripheral surface shapes thereof fit to the lower surface shape of a rear seat 102. However, such an example is insufficient for the versatility and so is not satisfactory.